The Aural Exciter is an old technology.Back in tape days,highs tended to fade away (ever put a cymbal on an edge track?) and the Aphex generated artificial harmonics to add some sparkle back in (normally used on vocals).Frequency response is so much better with today's digital technology that the need doesn't exist as it did then.
The BBE claims to "tighten" the signal,B.S. in my personal opinion.The bass speaker voice coil is several inches further from your ears than the tweeter voice coil,supposedly leading to minor phase problems which the Sonic Maximiser corrects by splitting the signal with an internal crossover, then slightly delaying the treble component to "time allign" them.Uh huh,right...caveat emptor.
Tom